Published Date: 2010-05-06 03:00:11
Subject: PRO/EDR> Melioidosis - Australia (03): (NT)
Archive Number: 20100506.1467
MELIOIDOSIS - AUSTRALIA (03): (NORTHERN TERRITORY)
A ProMED-mail post
is a program of the
International Society for Infectious Diseases
Date: Wed 5 May 2010
Source: Australian Broadcasting Corporation [edited]
A dangerous bacteria found in soil has claimed the lives of 10 people in
the Northern Territory, the [Australian] Centre for Disease Control says.
Melioidosis [caused by _Burkholderia pseudomallei_] usually strikes during
the northern Australian wet season, which runs from about November until
April. The centre's acting director, Dr Peter Markey, says about 20 to 30
infections usually occur each wet season, resulting in between 2 and 4 deaths.
But Dr Markey says this wet season has seen the number of infections surge.
"This year we've had 72 cases so far," he said. "That is over 3 times [what
we would normally expect] and well ahead of any other season that we've
had. And 10 of those people have sadly passed away from the melioidosis."
He says all of the people who have died have been aged over 30 and had
pre-existing medical conditions, including diabetes, lung disease, and
alcohol problems. Dr Markey says melioidosis infections had occurred in
urban and rural areas of Darwin, in Arnhem Land, in Katherine, and in
Central Australia. "The bacteria live in the soil in the tropics and people
can become unwell either inhaling the bacteria if they come into close
contact with it or acquiring the infection through the skin via a cut or a
[byline: Jano Gibson]
[Melioidosis is a disease of the rainy season in the endemic areas. It
mainly affects people who have direct contact with soil and water. Many
have an underlying predisposing condition such as diabetes (commonest risk
factor), renal disease, cirrhosis, thalassemia, alcohol dependence,
immunosuppressive therapy, chronic obstructive lung disease, cystic
fibrosis, and excess kava consumption. Kava is an herbal member of the
pepper family that can be associated with chronic liver disease.
Melioidosis may present at any age, but peaks in the 4th and 5th decades of
life, affecting men more than women. In addition, although severe
fulminating infection can and does occur in healthy individuals, severe
disease and fatalities are much less common in those without risk factors.
In a rodent model, a higher inoculum can greatly increase mortality rates
even in immunologically normal hosts.
The most commonly recognized presentation of melioidosis is pneumonia,
associated with high fever, significant muscle aches, chest pain and --
although the cough can be nonproductive -- respiratory secretions, which
can be purulent, significant in quantity, and associated with on-and-off
bright red blood. The lung infection can be rapidly fatal -- with
bacteremia and shock -- or somewhat more indolent.
Acute melioidosis septicemia is the most severe complication of the
infection. It presents as a typical sepsis syndrome with hypotension, high
cardiac output, and low systemic vascular resistance. In many cases, a
primary focus in the soft tissues or lung can be found. The syndrome,
usually in patients with risk factor comorbidities, is characteristically
associated with multiple abscesses involving the cutaneous tissues, the
lung, the liver, and spleen and a very high mortality rate (80-95 per
cent). With prompt optimal therapy, the case fatality rate can be decreased
to 40-50 per cent.
A map of Australia showing the location of the Northern Territory can be
found at <http://www.staffordmall.com/media/australia-map.gif>. - Mod.LL]